Associer productions animales et végétales : quelles limites des approches fondées sur des systèmes spécialisés pour concevoir des outils de diagnostics et accompagner les polyculteurs-éleveurs dans une transition agro-écologique ?

Ce numéro d'Innovations Agronomiques rassemble des articles issus de communications présentées au colloque national «Les polycultures-élevages: valoriser leurs atouts pour la transition agro-écologique » organisé par le RMT SPyCE et AgroSup Dijon, à Dijon les 10 et 11 octobre 2017.Mixed farming systems are identified as examples of agro-ecological systems. However, the extensionof these modes of production is not easy. Based on feedback from two projects, one on the design of anagro-ecological diagnostic tool for farms (diagagroeco) and the other on support for groups of farmers intransition (DECO AGRO -ECO), the article highlights the methodological hurdles encountered in thedesign of diagnostic tools adapted to mixed farming systems and the support of farmers with inputsdesigned for specialized farms.Les systèmes de polyculture-élevage sont identifiés comme des exemples de systèmes agroécologiques. Pour autant, le déploiement de ces modes de production n’est pas évident. A partir deretours d’expériences autour de deux projets, l’un sur la conception d’un outil de diagnostic desexploitations (diagagroeco) et l’autre sur l’accompagnement de groupes d’agriculteurs en transition(DECO AGRO-ECO), l’article met en évidence les freins méthodologiques rencontrés lors de laconception d’outils de diagnostic adaptés aux exploitations en polyculture-élevage et del’accompagnement de polyculteurs-éleveurs avec des entrées conçues pour des exploitationsspécialisée

LE CONSEIL AGRICOLE AU CARREFOUR DU DEVELOPPEMENT SECTORIEL ET DU DEVELOPPEMENT TERRITORIAL :ACCOMPAGNER L'ACTIVITE AGRICOLE EN SITUATIONE

N° ISBN - 978-2-7380-1284-5International audienceThis paper provides a framework to analyse the undergoing changes in agricultural and rural development. As a result of these changes, agricultural extension is faced with the challenge of standing at the crossroads between sector development and territorial development, which is the issue analysed here. This paper contributes to a new conceptualization of agricultural activity, reaching beyond its technical, economic, and productive aspects so as to include cultural and political factors, as well as the spatial and time dimensions related to local and daily life activities. This leads to the establishment of a new approach of agricultural changes and their accompaniment, and of public policy guidelines, which places collective actions, together with their situated dimension, purposes, and knowledge, at the heart of the analysis. The subsequent conceptual framework has being tested in a number of French studies, which first results, reported in Part 2, can be synthesized as three major trends: territorial factors are progressively being integrated in agricultural advice, including in traditional farming sectors; the public and the objects of agricultural extension are diversifying; extension agents need to cooperate with the development agents of non-agricultural sector. All in all, the skills of the extension agents, and their ability to facilitate collective actions, are the most sensitive issues brought about by these new challenges

The Logarithmic Sobolev Constant of The Lamplighter

We give estimates on the logarithmic Sobolev constant of some finite lamplighter graphs in terms of the spectral gap of the underlying base. Also, we give examples of application

Revealing the reporting disparity: VigiBase highlights underreporting of clozapine in other Western European countries compared to the UK

Background: Pharmacovigilance studies indicate clozapine history is marked by adverse drug reactions (ADRs). Objective: In a 2021 article, the United Kingdom (UK) had >90 % of European clozapine-related fatal outcomes in VigiBase, the World Health Organization's pharmacovigilance database. Two possibly opposing hypotheses could explain this disparity: 1) fewer reported fatal outcomes in other Western European countries mainly reflect underreporting to VigiBase, and 2) the higher number of UK reports reflects higher real relative mortality. Methods: VigiBase reports from clozapine's introduction to December 31, 2022, were studied for ADRs and the top 10 causes of fatal outcomes. The UK was compared with 11 other top reporting Western countries (Germany, Denmark, France, Finland, Ireland, Italy, Netherlands, Norway, Spain, Sweden and Switzerland). Nine countries (except Ireland and Switzerland) were compared after controlling for population and clozapine prescriptions. Results: The UK accounted for 29 % of worldwide clozapine-related fatal outcomes, Germany 2 % and <1 % in each of the other countries. The nonspecific label "death" was the top cause in the world (46 %) and in the UK (33 %). "Pneumonia" was second in the world (8 %), the UK (12 %), Ireland (8 %) and Finland (14 %). Assuming that our corrections for population and clozapine use are correct, other countries underreported only 1-10 % of the UK clozapine fatal outcome number. Conclusions: Different Western European countries consistently underreport to VigiBase compared to the UK, but have different reporting/publishing styles for clozapine-related ADRs/fatal outcomes. Three Scandinavian registries suggest lives are saved as clozapine use increases, but this cannot be studied in pharmacovigilance databases

La télédétection des infrastructures agro-écologiques : de la promesse aux méthodes opérationnelles (Tél-IAE)

Les infrastructures agro-écologiques comme les haies et les bandes enherbées sont des éléments paysagers clé pour la biodiversité dans les territoires agricoles. Les cartographier est une étape importante pour évaluer la qualité des paysages et prédire l’impact d’aménagements. La télédétection spatiale présente un potentiel important pour atteindre cet objectif à coût raisonnable et sur une surface importante. Le projet « télédétection des infrastructures agroécologiques » regroupant spécialistes de la télédétection et utilisateurs s’est proposé d’évaluer des méthodes existantes dans des cas variés et d’en développer de nouvelles. Un site web présentant les résultats du projet guide l’utilisateur vers des grands types d’options techniques en fonction de son projet et lui donne accès à diverses ressources. La pleine appropriation des méthodes et outils implique toutefois un décloisonnement des métiers au delà des considérations purement techniques

Estimating time-to-onset of adverse drug reactions from spontaneous reporting databases.

International audienceBACKGROUND: Analyzing time-to-onset of adverse drug reactions from treatment exposure contributes to meeting pharmacovigilance objectives, i.e. identification and prevention. Post-marketing data are available from reporting systems. Times-to-onset from such databases are right-truncated because some patients who were exposed to the drug and who will eventually develop the adverse drug reaction may do it after the time of analysis and thus are not included in the data. Acknowledgment of the developments adapted to right-truncated data is not widespread and these methods have never been used in pharmacovigilance. We assess the use of appropriate methods as well as the consequences of not taking right truncation into account (naïve approach) on parametric maximum likelihood estimation of time-to-onset distribution. METHODS: Both approaches, naïve or taking right truncation into account, were compared with a simulation study. We used twelve scenarios for the exponential distribution and twenty-four for the Weibull and log-logistic distributions. These scenarios are defined by a set of parameters: the parameters of the time-to-onset distribution, the probability of this distribution falling within an observable values interval and the sample size. An application to reported lymphoma after anti TNF-¿ treatment from the French pharmacovigilance is presented. RESULTS: The simulation study shows that the bias and the mean squared error might in some instances be unacceptably large when right truncation is not considered while the truncation-based estimator shows always better and often satisfactory performances and the gap may be large. For the real dataset, the estimated expected time-to-onset leads to a minimum difference of 58 weeks between both approaches, which is not negligible. This difference is obtained for the Weibull model, under which the estimated probability of this distribution falling within an observable values interval is not far from 1. CONCLUSIONS: It is necessary to take right truncation into account for estimating time-to-onset of adverse drug reactions from spontaneous reporting databases

Numerical Investigation of the Performance of Three Hinge Designs of Bileaflet Mechanical Heart Valves

Thromboembolic complications (TECs) of bileaflet mechanical heart valves (BMHVs) are believed to be due to the nonphysiologic mechanical stresses imposed on blood elements by the hinge flows. Relating hinge flow features to design features is, therefore, essential to ultimately design BMHVs with lower TEC rates. This study aims at simulating the pulsatile three-dimensional hinge flows of three BMHVs and estimating the TEC potential associated with each hinge design. Hinge geometries are constructed from micro-computed tomography scans of BMHVs. Simulations are conducted using a Cartesian sharp-interface immersed-boundary methodology combined with a second-order accurate fractional-step method. Leaflet motion and flow boundary conditions are extracted from fluid–structure-interaction simulations of BMHV bulk flow. The numerical results are analyzed using a particle-tracking approach coupled with existing blood damage models. The gap width and, more importantly, the shape of the recess and leaflet are found to impact the flow distribution and TEC potential. Smooth, streamlined surfaces appear to be more favorable than sharp corners or sudden shape transitions. The developed framework will enable pragmatic and cost-efficient preclinical evaluation of BMHV prototypes prior to valve manufacturing. Application to a wide range of hinges with varying design parameters will eventually help in determining the optimal hinge design

Subsequent and simultaneous electrophysiological investigation of the retina and the visual cortex in neurodegenerative and psychiatric diseases: what are the forecasts for the medicine of tomorrow?

Visual electrophysiological deficits have been reported in neurodegenerative disorders as well as in mental disorders. Such alterations have been mentioned in both the retina and the cortex, notably affecting the photoreceptors, retinal ganglion cells (RGCs) and the primary visual cortex. Interestingly, such impairments emphasize the functional role of the visual system. For this purpose, the present study reviews the existing literature with the aim of identifying key alterations in electroretinograms (ERGs) and visual evoked potentials electroencephalograms (VEP-EEGs) of subjects with neurodegenerative and psychiatric disorders. We focused on psychiatric and neurodegenerative diseases due to similarities in their neuropathophysiological mechanisms. Our research focuses on decoupled and coupled ERG/VEP-EEG results obtained with black-and-white checkerboards or low-level visual stimuli. A decoupled approach means recording first the ERG, then the VEP-EEG in the same subject with the same visual stimuli. The second method means recording both ERG and VEP-EEG simultaneously in the same participant with the same visual stimuli. Both coupled and decoupled results were found, indicating deficits mainly in the N95 ERG wave and the P100 VEP-EEG wave in Parkinson’s, Alzheimer’s, and major depressive disorder. Such results reinforce the link between the retina and the visual cortex for the diagnosis of psychiatric and neurodegenerative diseases. With that in mind, medical devices using coupled ERG/VEP-EEG measurements are being developed in order to further investigate the relationship between the retina and the visual cortex. These new techniques outline future challenges in mental health and the use of machine learning for the diagnosis of mental disorders, which would be a crucial step toward precision psychiatry

Simulation of the Three-Dimensional Hinge Flow Fields of a Bileaflet Mechanical Heart Valve Under Aortic Conditions

Thromboembolic complications of bileaflet mechanical heart valves (BMHV) are believed to be due to detrimental stresses imposed on blood elements by the hinge flows. Characterization of these flows is thus crucial to identify the underlying causes for complications. In this study, we conduct three-dimensional pulsatile flow simulations through the hinge of a BMHV under aortic conditions. Hinge and leaflet geometries are reconstructed from the Micro-Computed Tomography scans of a BMHV. Simulations are conducted using a Cartesian sharp-interface immersed-boundary methodology combined with a second-order accurate fractional-step method. Physiologic flow boundary conditions and leaflet motion are extracted from the Fluid–Structure Interaction simulations of the bulk of the flow through a BMHV. Calculations reveal the presence, throughout the cardiac cycle, of flow patterns known to be detrimental to blood elements. Flow fields are characterized by: (1) complex systolic flows, with rotating structures and slow reverse flow pattern, and (2) two strong diastolic leakage jets accompanied by fast reverse flow at the hinge bottom. Elevated shear stresses, up to 1920 dyn/cm2 during systole and 6115 dyn/cm2 during diastole, are reported. This study underscores the need to conduct three-dimensional simulations throughout the cardiac cycle to fully characterize the complexity and thromboembolic potential of the hinge flows

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements